Question

所以，我有这个类，我调用了几个检查数据的类。他们返回一个名为Failcase的错误类。现在，当我第一次将错误设置为true时，出现错误。

错误说明：

无效使用财产。

Private Sub btnImport_Click()
    Dim fail As Failcase
    Set fail.Success = True       '<---- This is where the error occures

    Set fail = ImportCheckSpec(Me.txtImportSpec)

    If fail.Success Then
        MsgBox "Error " + CStr(fail.Code) + ": " + fail.Message, vbCritical, "Error"
        Exit Sub
    End If

    Set fail = ImportCheckDate(Me.txtDateTime)

    If fail.Success Then
        MsgBox "Error " + CStr(fail.Code) + ": " + fail.Message, vbCritical, "Error"
        Exit Sub
    Else
        MsgBox "Success"
    End If
End Sub

Failcase类看起来像这样：

Option Compare Database
Option Explicit

Public Success As Boolean
Public Code As Integer
Public Message As String

我用：

Microsoft Access 2013
VBA

Answer 1

您正在使用OOP而不创建类Failcase的新对象。在模块中尝试这个：

Option Explicit

Public Sub TestMe()

    Dim fail As New failcase
    fail.Success = True
    Debug.Print fail.Success

End Sub

在课堂上：

Option Explicit

Private m_bSuccess As Boolean

Public Property Get Success() As Boolean

    Success = m_bSuccess

End Property

Public Property Let Success(ByVal bNewValue As Boolean)

    m_bSuccess = bNewValue

End Property

因此，您将实现封装。有了它，您可以为访问您的媒体资源设置更多规则 - https://www.google.com/search?q=encapsulation+oop&oq=encapsulation+oop&aqs=chrome..69i57j0l5.3599j0j7&sourceid=chrome&ie=UTF-8

上面的代码是early binding的示例。这是另一个，后期绑定的例子，做同样的事情：

Public Sub TestLateBinding()

    Dim fail As Object
    Set fail = New failcase
    fail.Success = True
    Debug.Print fail.Success

End Sub

早期和晚期绑定具有不同的优点和缺点。

Answer 2

就像这样。

Dim fail As New Failcase
fail.Success = True

Microsoft Access VBA无效使用属性错误

2 个答案: